Falcon is ... ...an Open Source, simple, fast and powerful programming language, easy to learn and to feel comfortable with, and a scripting engine ready to empower mission-critical multithreaded applications. Falcon provides six integrated programming paradigms: procedural, object oriented, prototype oriented, functional, tabular and message oriented. And you don't have to master all of them; you just need to pick the ingredients you prefer, and let the code to follow your inspiration.

Quercus is Caucho Technology's fast, open-source, 100% Java implementation of the PHP language (requires JDK 1.5).

like procesing, etc

jGRASP is a lightweight development environment, created specifically to provide automatic generation of software visualizations to improve the comprehensibility of software